Grease trap



S. F. RESAN GREASE TRAP Sept. 23, 1952 Filed May 18, 1946 '7 Sheets-Sheet 1 S. F. RESAN v sept. 23, 1952 GREASE TRAP '7 Sheets-Sheet 2 Filed May 18 1946 m. a i

S. F. RESAN GREASE TRAP Sept. 23, 1952 '7 Sheets-Sheet 5 l Filed May 1a, 194e S. F. RESAN GREASE TRAP Sept. 23, 1952 7 Sheets-Sheet 4 Filed May 18, 1946 /Illllllllllll Sept. 23, 1952 Q F- RESAN 2,611,488

GREASE TRAP Filed May 18, 1946 '7 Sheets-Sheet 7 IN VEN TOR.

Patented Sept. 23, 1952 GREASE TRAP Stephen F. Resan, Elgin, Ill., assignor to Woodruff &"Edwards, Inc., El

of Illinois gin, Ill., a corporation Application' May 18, 1946, Serial No. 670,659

17 Claims. (c1. 21o-43) This invention relates to the separation of mixtures of immiscible materials having different surface tensions.

Broadly, the invention is directed to the separation of a Vdispersion or emulsion `of insoluble materials by means of selective surface tension effects.4 Y

1 To this end, the invention is directed to the separation of insoluble liquids by means of hydraulic filtration.

A specific embodiment of my invention may be in the form of an improved grease trap which operates upon the combined principles of gravity and surface tension separation. VIt will, however, .be understood that the invention may readily be 'adapted to other uses, and hence, the invention is not to be limited tor grease traps solely.

I have discovered a means whereby very fine or colloidal dispersions or emulsions of liquidliquid or liquid-solid materials may be rapidly and eiiiciently separated. The principle of my new separating process s based upon surface tension phenomena. Different liquids have different surface tensions. The surface tension of a liquid material depends upon the degree or amount of attraction between the individual molecules of the liquid within the liquid medium. By allowing a stream of an emulsion or dispersion of insoluble materials to contact a bed of surfaces having` predetermined surface tension properties, theremay be obtained a selective surface tension-'separatingfefiect wherein one of the ingreclients in the dispersion or emulsion will vbe selectivelydeposited upon these surfaces.

By means of the 'above surface tension phenomenon, itbecom'es ,possibleto apply a different principle of ltrationy namely, the application of hydraulic filtering to the separation of insoluble liquids or materials. The invention contemplates that the filter elementlmay also be one `of. the inf soluble liquids which it is desired to collect. Thus, a mixture of water and oil may be brought into proper contact with either an oil layer to serve as a lter 'element or a Water layer to serve 'as` a filter element, depending upon which is to be separated and collected in a vessel.` If it is desired to collect oil 1in a vesselwhich receives a mixture of oil and water wherein water is the dominant liquid, then the filter element or filter layer may be oil, and this may be located at or near the surface of the hydraulic filter vessel. If the desired action is to be reversed, namely, the `mixture contains oil as the dominant liquid, then the filter layer or filter element may be water, and this may. be located at or near the bottom of the hydraulic filter vessel. The water-in-oil emulsion can then be directed to flow upwards through the hydraulic 'filter element, namely, water, to collect the water.

The preferred form of my hydraulic lter element is that of a series or nest of parallel pipes, rods or tubes. The surface of these pipes or rods should be such as to exercise a preferential selective surface tension effect on one of thewater immiscible liquids. For grease trap punposes, where there is av mixture of water and oil, such mixture may be directed under uniform fiow but in a non-turbulent condition to a layer or nest of parallel iron pipes. As the liquid mixture drops onto the nest of iron pipes, it will divide into amixture consisting of globules of water and globules of oil or grease. The material'which is nominally fed to grease traps consists of a Yliquid dispersion or emulsion wherein the oily material is the minor ingredient and the water the major ingredient. Under such circumstances, any globules of grease or oil, which are Within the globules of water surrounding the oil, will tend to fiow to the surface of the Water globule because of the difference in spe-cie gravity. The surfaces of the pipes have a preferential surface tension effect for the'oil over the water. This results in greater wetting power of the oil for the :pipe surface.` Because of this existing preferential force, the globules of water which contain small globules of oil or grease 'at their surface will be subjected to a separating effect upon coming in contact with the pipe surfaces, with the result that the globules of oil at the surface of the globules of Water will be removed and deposited in the form of Van oil or grease layer on the nest of pipes.

The hydraulic filter herein disclosed is basically different from the filters heretofore used. Although the lter `element is one of the insoluble liquids which it is desired to collect, funda.'- mentally the finely divided particles in the mixture are brought into intimate contact withA the main body of the filter. Where the mixture is of grease and water and the dominant fiuid is water, the filtering layerrwill be grease. The formation of the filtering layer is initially formed about the tension tubes by the preferential surface effect of the latter for the grease. Continued flow of the mixture results in any grease in the globules of the mixture coming to the surface of the globules and adhering to the filtering bed which remains about the tubes by the retaining force exerted by the tubes on the grease layer and by gravity.

1 eig. 1e

Several preferred forms of structure are dis closed herein, but it is found desirable to reduce the velocity of the mixture and to liberate the air therein and cause it to escape to atmosphere. vAir blub-bles within the mixture-cause turbulence and they should be eliminated as rapidly as possible. To thisv .end .the invention is embodied in one of its preferred forms in apparatus conducting the incoming jet of high velocity mixture into a longitudinal channel to cause the iniluent to impinge against a portion of the tension tubesV whereby the mixture will distribute itself v'more uniformly in velocity and the velocity will be reduced Vin Vmagnitude.

in the escape of air contained in the mixture by Thi anansementfq structure to effect a reduction in velocity results* i inuent may enter at opening 2 in front wall 4 causing the air to rise to thesurface. Further:

reduction in velocity may be effected tc insure the escape o-f lair by the..,use of bufngmeans'in any suitable form, as by diverging walls, to dithe `kinetic energy of ow. 'Theruse-oweirs may lchange' the direction of flow,' which may-'Ibercverse tothat of the influent, so as tocause the' mixture-to fall upon the tension ftubesandthe is filtering bed the-reabou't.

vide the flow 'and to distribute more uniformly 'The invention is concerned-with structure that y keepsl the velocity of the mixture owing through the filtering zbed low enough so that therorces caused by' the kinetic energy will not teartfhe grease awayifro'm the tension tubes. lI'hus, "the structure should be oiI a Acharacter that the velocity of the m'ixturefbe maintained at a Ypoint where'the dislodging force of the Vincoming mixture will not overcome `the retaining force exerted lby .the tension tubes on the greaselayer, but ithisfvelocity should be enough to release the `collecting.grease at .the lter .bed in solidified or vs'enii-solidified agglomerates or masses thatmay move Iawa-y from the bottom r,and rise" to a collecting -charrrber`V Vin, the" apparatus.

`Examples .of inimiscilble 'liquid emulsions which may be separatediinto their individual vcomponents .bymeans of -the-abovedescribed type y 4of `apparatus .are mixtures of oil and water,

y petroleum and jwater, water and mercury,V glyclerin and carbon tetrachloride, water and carbon tetrachloride, ywater and carbon disulphide, and turpentine andwater. 1

:.:Referring :now :to the drawings,

v'Ii'igfl =a `plan view :with the topy cover removed, 'showing la hydraulic lter construction .designed as fa grease trap wherein thehydraulic filterserves as la. .grease layer lter element, a

:portion of the structure illustrating the jflowof the iniluent;

V"Fig..la is a top- View, at reducedxscale, :of the cover.; y

.Fig; 12 is a .cross section `taken onv line 2-'2 of dFlieg-.1; Fig '3 isla cross section taken on line 343 -oi Fig'isj :Je K *e* 1 Fig.` 4 lis' a cross section' taken rOnline -lof Figl; y n

Fig'. i5 `is a perspective view ofthe lhydraulic fltentype grease vtrap illustrated in Figs, l through 9; v

Eig.L 6`is *a cross section' takenon '-lin-e- 5--5 of Eig. 7 is a crosslsec'tion'taiien-on line '1 -"lof Figi; y i 1 Fig an end `view partly in elevationand partly in section looking in the direction or' the arrows along line 8--8 of Fig. 1; l

for housing il and flow through .a longitudinal channel 3. Channel 3 may be dened by two vertical side walls 5 and S. suitably supported'to fextend'inwa'r'dly .from front wall 4 to meet and l join .we-irs 1 and 8 disposed transversely in housing I and forming a part of aV unit in which a cross. channel `I4 is provided, which unit includes-.an arcuate base or floor-'l'v'andI-a wall 9 disposed preferably parallel tofwei'r-s 'I 'and lil. Channel 3 isalso provided with -an arcuatebase or iloorfll which maybe `integrally -or otherwise formed with side walls-5 and-6, opening' being so'related withrespect to these parts-that the inuent entering opening 2 will not overiiow the top edges I2 andi 3 of side=walls--5ffand 6, the latter being cut away lat these edges, ji'f'r'so desired, and lower than the wellig.'

'Side walls Sjand 6 continue-forwardly*across lateral channel 'I4 attheir upper part `'in diverging relation, `wings l5 and 'lbeinglformed-which preferably engage against wall -9 Vandvleave Aopenings "therebelow to `permit-'channel 'i4 to be 'continuous ,crosswise so that the Vinfluententering longitudinal vrchannel 3 will "flow in vopposite'dhirections through channel 1,4 `and rise to Y over- .ilow weirs 15a-nd 8. Weirs'f'lfjand 8are preferably, although -not necessarily, of less height than walls 5 and 6and are Vof Acourse of 'less height than their lopposing parallelwall.

. As wil1 ,be later explained, Vthe 'specific em'bo'd ment of the rinvention .disclosed in Figs. 1 to `9, inclusive, is shown with weirs 1rand 8`consider, ably. lower than wall 9 `andat or about the level ofJthe'iower edge of .the `outlet 'openingjof housing `rI gfroprovide a filter bed'ror the insoluble iqi'l.

Aor material to be .filteredout ,of the'mixture,fa plurality of cross pipes designated broadly as 'I8 are provided to lie crosswise of'longitudinalchan-- nel `3 and ol two 'chambers I`9 .and 26 formed on. opposite sides ofchannel .3 'betweenweirs I Aand 8 and 'front'wall 4 and the sidewalls 2'I Y'and 22 of housing l. The relative positioning ollpipes' I8, which maya-lso lbe termed tension tubes,` will be clearlyseenin Figs. 2, ,ei` and`5. Thesefpipes 18. mayV bejof iron when grease .isto'be filtered and .are preferably passed through openings in 'sidewalls 5 and 5, eitherto enter openings inr `side wall'sjZl and`22 of casing l Afor support or 'to abut against side walls "21 and 22. neither 9&5?, pipes I8 are dispersed 'in a manner 'causing the'lmixtule overflowing weirs '1 and 8 'to "fall Voverand upon them 4so that this mixture will be caused to flow through the filtering bed formed bythese `pipes and on which the materialto be ltered'collects .toform afilteringlayer, 1f theV size -of, chambers i9 and 20-Warrants, two verttica1irqws-ofpipes I3 are/provided, therios'f each row .being staggered withrespectto the pipes of the-other row, the arrangement assuring` that it Aall flows, as will be later explained in c'obn'nec vtion N'with the operation, the -miXture'jwill Vbe inI accordance withthelnature of the insoluble liquid or material of themixture to be filtered.

Below the separating chambers I 9 and l20 there is the main body 24 of housing I. The grease or other separated insoluble material breaks away fromthe filtering bed in agglomerates oi varying sizes fand. accumulates at the top of the collecting chamber 25, the liquor owing to outlet opening 26, as illustrated in Figs. 2` and 3, at the bottomofhousing I. l t" Opening 26V connects with a vertical passage 21 formed in the rear wail' 2.a 'of-housing i. Rear' 4 wallf28 `hasj-'an outlet opening 29 therein to which may beattached the fitting forming the outlet connection (not shown). I1`fhe other Wall30 of passage 21 is a part of a wall3I in which opening 26 is provided, wall 3| having a second opening f 32 communicating with a chamber 33 dened by a vertical Wall 34 and a floor 35. ,Chamber 33 may communicatel withV either top opening 36 orside opening 31, both being threaded or otherwise provided for a connection to atmosphere. 1 Ifr the locationof housingl does not admit of atop fconnection with opening 36, -a plug (not shown) willbe'used tocloseoi opening 36and a con-A nection will be made with side opening 31. The reverse connections may be made with the plug closing off side opening 31. Within chamber 33 are two vertical walls extending slightly above the top` edgel33 of opening 32, the front wall 40 and Y,

thefside wall 4I. These walls 40 and 4I form` a separate chamber A42 Within chamber 33 which:`

communicates with chamber 33 at a level abovey` top edge 39 of opening 32 (see l'figs. 7 land 8) the wal1s40 and 4Ibcing spaced from the walls of' chamber l33 vso that chamber 42 will be open to communication Without clogging with chamber 33. Chamber 33 communicates with chamber 24V' byopening 32 and chamber 42 communicates with 'passage 21 by a vertical passage 43 which lterminatesat its lower end slightly lower Ythan the bottom of outlet opening 29, chamber 42 also communicating either with top opening 36 or with side opening 31.

On the other hand, passage 21 not only communicates with outlet opening 29, but also withV a top opening' 44 and with a side opening 4,5. De-V pending'uponlthe installation, a vent connection- (not shown) is made with either while the other is plugged. Sewer gases sometimes tend to enter a grease trap and flow backwardly through the inlet connection 2 and its connectiontoV the sink or tank. `In. the present structure, vent connec` tions 44 o-rf45V tend to prevent this occurrence and also tend to prevent an undesirable accumulation of gas"pres`si"1re`ff1f this pressure increased? inthe upper part of passage'21 inthe instantdee" vice, the `normal non-flow level of the liquor in passage 21 might be depressed to breakfthe--liquid sealV at the `bottom of passage 43, thereby allow?" ingthisgas to enter chamber '24 and flow back wardly through the sink drain. Vent connections i at 44and 45 Willprevent this pressure from build-rv ing up.

`Passage 43 and chambers `42 and 33 form anti# siphoning means that will prevent any siphoning of the liquor in chamber 24 through outlet open-":

ing 29, 'this beingv true whether either opening" 36 or 31 is connected to atmosphere or is plugged: i

6 As soon as the levelof the liquor is below pas-Y i sage 43 so that it is open to passage 21, air either from chamber 24 or from `vent connections at' tached to openings 36 or. 31 will owfto outlet connection 29, either through opening 32 from' chamber 34 or through chamberV 42 from thesev said connections, andthe 'siphoning action of the liquid will 'be broken.` i. Y. i Cover 45' illustratedin top plan'view in Fig laand iny position on housing IV in Fig. 4v pro-\ videsfa gastight sealfor chamber 24. It'mays? be easily removed for permittingthe clear'iing of chamber 24 without disturbing the vent coni nections l-to top; openings 36 and' 44 orwto side openings 31 and 45. By providing bolts 46 havingu handles 341, it is possibleto provide' slots 48 inL coverr45 which will receive these bolts and'per# mit ready manipulation of the handles to thread the bolts into openings 48' along the top edge of housing I Wherebyfthe` cover may be quickly clamped upon the housing in tight relation." `If so desired, a, gasket 49.' may be used to assurea gas tight seal. a t

The structure dening longitudinal channel 3 and lateral channel I4may be formed as a unit forl insertion 'or removal fromV housing I-.f` Whether the weirs 1 and 8, Wall 9 andliloo'r ID are cast or formed in' a `single piece and the side walls 5 and 6, their floor II and diverging walls I5 and I6 are likewise cast or formed'in a, single piece, these parts maybe first formed' and at-l y tached together, with tension tubes I8 mountedV` crosswise in walls 5 and 6, before they'areinserted in housing' I. Their arrangement permits a unitaryA relation that greatly facilitates' the -in" sertion and removal of this filtering part of thev device disclosed herein because Aany suitable Y mounts suchk as shoulders or lugs 56 may bewcast or otherwise providedon side walls 2l landV 22'! of housing! and have inwardly sloping topv ledges 51 which tendto hold the filtering unit against front wall 4 and in operative relation withinl'etf opening 2. A forward 'mount 5'8"`on frox'itrwallz 4 may receive the front edge of floor IVI so thatl the structure will be suitably 'supported at this point. Thus, this filtering structure ymaybe readily lifted out of housing I for cleaning.

It will be observed 'that floors IIl and 'Ill of passages 3 and' VI4 are curved. It`- is found that curving these'iioors tends to preventeddycurf-- rents setting up in theincomng mixture and to'V reduce turbulence. A quiescent state tends to-1` liberate trapped airfrom the mixture iivhi'chis"v desirable Vto accomplish before the mixture spills4 upon the tensiontubes or filtering bed formedv about thetension tubes. -V i As to the operation of the device disclosed in Figs. 1=to 9, inclusive, Awhen it is used as' a'greasef trap, kitchen sink drainage consisting generally of a minor portion-of oil and a major portionv of water will enter `longitudinal channel 3-'at relative high velocity and will impinge-against the portion of 'tension tubes I8 lying cro'sswise'v thereof. As the jet of high velocity mixture impinges said tubes, it is distributed more uniformlyV as to velocity, and, after vpassing through the tubes, the velocitywill be reduced.; Thsredu tion of velocity makes it possible forv the air contained Within the mixture to rise tothe surface and to escape to theatmosphere. Air bubbles` within this mixture cause turbulence, `and there-rv fore, they should be eliminated as rapidly as pos4 sible. In Fig. 2, the air bubbles are indicated-ati` as hollow white circles Whilethe grease oroili to be separated is indicated at 5I. as solidblackn? particlespthe surrounding portionfin Whitezbeing.`

water-:.and: otherforeign matter that@ .may :be 4in thetmixturexr..Asztheimixture proceeds .tolth'e end oflongitudinalwhannel 3,?diverging .Waller-.I 5 and I 6'. further reduce .the .velocity'by'dividing `.theflow 'i andizlcausingt iti to.' :',move'I vin .ifopp'osite directions ythi-tough":cross.follan-ziel If4'; rltherebyfurther: assur-1- Y ing a thorough escape offaiiiibubbles'zThewalls 5 and 6 Tof-longitudinalzchannelzBtare? sufficiently outletfopening so that the liquidV level-:wil-lber` held slightly below the top of weirs .1 andfwhen the dev-icefisgdormant: It Will be observed that the top .edgeoff weirs.' 1 andf isl jat .a leveltabiout equalgto :the-centeri of: lowerfftension fpipe I3 in the; right-hand :row as viewed inlig. 4.-. Y At a low r rategofeow ofv theinfluent, the' mixture `will spill oteraweirsfl and. 8; and bebroughtvinto .intimate contact vwith? thispipef'i4 or.j the .':gr,ease layeri.' deposited thereon.'.. Ati afslightly increased rate. they-,mixtureyvvillfiiowfoveithis lower-'pipe I8 Yof thelfright-hand row'and willralso be .brought into,

contactivvithLbothgpipes t8 of the lefthand rowi-v or the. greasea `:layer deposited-VVF thereon. Atzfull capacity. owftheeleyel i-oiy the'fmixture'v in cross channel-1 :i 4 will rise and the spill will reachfthe. height foffthe nig-hen 'pipe;.;lj8xof .vzthe right hand might alsoiA be. used;

oil... orf: grease due .to .the fgreaterwetting power of oilUor-agrea-se fori-iron.v When a .coating orlayerv oioilisr deposited-on the "iron rsurfaces- (pipes -l 8 )f, a. this oi1- layer-functionst .furtherffas` .a hydraulic. nlter;.-for-the; oil globules in the emulsionI as. the `emulsionflows;downward-overthe nestof these I surface V:tension .tubesfY Thisfhydraulic flteringm eiectisfdue to the .inter-molecular fattraction of the molecules in the oil layergdepositedfon their.

iron surface?. During the drop-of the.,oili=n.water emulsionfoventhe nest .offfsurface Y Vtension tubes;-V anyvpil f..('designated.' as '.53 and.` showns'in z black);- i which .may-be inside of the 'waterfg globulesf 52 of 'theeemu-lsidn-fwill 'come-tothe surface of thewvater?. globulesfbefore the emulsion passes throughethe goilflayendeposited' on theisurface-tension tubes-g As fthe-emulsionv mixture )of oilinwater :flows` oveiethe eoilcoatedI surfacetension-tubes,` thefioilfn layer deposited Vin 4the 4surface tension .tubes willi f tendf- ,to-:pull :apart:l and separate* the Aoil globules.; i froIIr.-..-th e v oil-.in-.water emulsion 1 passing, over; its is. surface-.5; Astthe stream ofremulsion" continuesxt .L beffe? .to rthe hydraulic-filter'separating'zappaef Iatumrthefoil. accumulates ;on" theiron pipe vsur:` facesf'andfthe; water, .drops :tothe `-bottoi'nf kof the.l chambenrZ 4.-; After: .a .suicient'aweight fofoil. ori f. grease;haszaccumulatedron thetironzapipesurfaces tocauseithezsametozdrdp.romithepipevsurfacesnz.

animee@ of. .'Certai-nffof-the-larger -.agglomerateswill. rise in chamberfuas'shownin Figs. 2 and ifandyacffin.k

Eig. 34) andY flowthereoveiand also` .over 1 Vthe.three.'remaining.pipes 18.-. The .arrangement ofithe-plpes. 18g-Shown iin Fig.=.4 y/resultsin Y a 'veryr eilicientilteringof-.thegrease from-the mixtureff; but itwillibeunderstood-thatother arrangements is foundgthatas vthefmixture'fleurs over'vvveirsf 1 and..Bfritlseparates andfformsvga multitudeifof I globulesmflhe rpipes l 8' act. as a ilter. layenforthe 8 the; detached: or: trapped. o ilf. or .fgreaseqzisz-v iintheret form;1of, .large agglomerates, .aas yShown. inf-Figs@ andfk 4.. The largegvagglomerates owwithpthe Watertofchamber- 24; andmoveto therrear.- there cumulate; asavlayer at .the topfk r'Ihe .watenwithfr anyl agglomera-tesY -remainingftherein.: will. img..- pinge'againstfwall 3 I., .v This slowsyupfthefilowrand therlemaining oila'ggl()merates areggivenample opportunity,f to @rise .fto the f surface lfand` form; continuouslayervofyoil or gigease, asfshown.. f ;'I'he watenvvhichisthe heavier.liquid, .remainsoni the betteln4 andf paSses--throuehfpenna 25. andftiienff.

The surface forces of attrac'ztifo V :winch- 'fareffa operating Qnzthe. pipe V'surfaces .to A:cause thefseparf ration of -the lighterxliquorf .fromgthe al'ieavier-r-` liquoizfare .-a'fcombinatipn ofi-two phenomena... Vl/"henishev emulsionA of the .two -irnmiscible liquida;-l

is firstcaused to flow 'downwardthroughthe bed... of. pipes, V.and- ,.whenf .the surfaces ..-of..these .-pipesf.. have notyet been contacted or coated',- the-surface f.: force; Which .is operatingis 'Y the v 10W I interfacial; fA

I tension. vbetwe en thefresh pipe surface and-.one y..

of'theimmisibleliquids of the emulsion..j In. this. particulate caser.nanriely,- Fii=,f,s 14 to .9,gthe-appan ratus Ais- .constructedfor an .emulsionf wherein-... the.v lighter. .zliquidmz is. the one having surface teny f.

v sion. and interfacial .tension-.properties l.bringingy about a selective coatingfordeposit of the lighter...

liquid on thepipesurface.;sWherpthe freshfpiper... I surface.hashad deposited a..thin .coatingrof the... f

lighter liquid component, there comes. into-.pla

f. another .surface-.attraction ...force namely, the..

forces of attraction between the..molecules..of thef lighter liquid... Thefintermolecular. forcepoi. at.;-

traction between.. the molecules colf. .the lighter liquidis r"greateigth'an thelintermolecular.forceof gattraction between themolecules ofthe other ini-,

miscible liquid v.being depositeden .thepipesurface...n Hence,..a -stifearnwofl .emulsion .owing.f through. the bed .of pipes i 8 Latter thepip'ef..sur fA faces have been initially. .coated .withtheli'ghten liquid@creates axconditionwherein the globulesof;`

lighter-...liquor ..in.. t he...moving .emulsion ref idily.i unite*` with. Vthe main. layer. or. coating.. of.. lighten. liquor. thathas alreadybeen depositedA onthe pipe;t surfaces. The. removal of, the lighter; liquorfromthe heavier liquor by means ofv-the-pipesurfaces.-` under .theA conditions described .is a very positive effect, because. the force holding, theflighterjliquor. globuleto theheavierliquer globulein the'infiu-z ent emulsion is-readily `overcome by -theforce jbeefff ltweenthemair-ilayer of lighter'liquor on theppev;

surface and-the globule; of flighter fliquor in. they: emulsionpassingethesame-. u g Y I The arrangement; shown in Figs. 10 pto 12,` inap-f elusive,A may ,be Aused- .Where theV emulsionmixe .ture consists of eitheriwater and'.V carbon.tetra,.;;z

'by 4baille walls lv andi by ther-open :baffle chambers enterichamber 66 between wall Gl'and averticalff be spaced from the walls of the housing offtl'ievfv device.i .Upon reaching chamber 65;.'ezth'e mixture will be forcedzupwar'dly ontozanestof Hsurface?.

tension. tubes. 69 similar zto'ethetubes. VI 8.. -The'sesi tubesfzhave .an outer-v surfacei-which iareieprefer-f.. -entiallymwetted bygcarbonctetrachlord onparbonz:

'material such as polystyrene,"etc. where the tubesv 69 were made of this plastic disulphide. `As the A emulsicrrmoves,4 upwards through this nest of horizontal ,tensiontubea the Vcarbon tetrachloride, or` carbon disulphide, due to its Vgreater wetting power deposits asa layer on the surface of the tubes, and then, passes on upwards through the nest of `tubes 69 and overflows over the wall 68, thereby entering the large chamber 10. Some of the carbon tetrachloride` orcarbon disulphide will vnot be caught by the hydraulic filtering eifect on the tension surface tubes and will be carried over with the water. Thel carbon tetrachloride or the carbon disulphide is, however, in the Aform of large agglomerates by the time the emulsion has passed upwards through the nest of tubes 69. `These agglomerates, Abeing distinctly heavier than water, readily settle to theA bottom of thelarge central `chamber l andthe water rises to the top of the chamber.` Baiile 1I tends further to slow up the flow of liquor through the grease l `trap and thereby bring about a more complete oil-water separation by givinghthe water more and water may also be treatedby the apparatus Y illustrated in Figs.A 10, 11V and l2. I have found,

however, thateit isV desirable to employ tension tubes having surfaces of either copper, brass, nickel, silver or gold when it is desired tolter the mercury out of the water because the wetting power of mercury for these metals is quite substantial and the mercury "will therefore readily* coat such surfaces for the tension tubes and thereby separate the mercury particles from the surrounding water particles as the mixture moves through the filtering layer deposited on the tube surfaces. It will be understood of course that the mercury will free itself i`n` substantial f sized `particles from the tension tubes as the deposit increases and will now over to the bottom of chamber 1D from where it can be removed;

Carbon tetrachloride is a liquidrwhich is immiscible with glycerine. The carbon" tetrachloride, which is a heavier liquid with a lower surface tension, has aY greater wetting power towards such a Vsolid surface as thermoplastic material, the carbon tetrachloride with a greater wetting power selectively coated the surfaces,

Viilteredout -of thewaterby the apparatus disclosed in Figs. 10, -lf andl2. Here, also, the tension tubes will have their surfaces of glass and the carbon disulphide deposited upon these glass surfaces, thereby becomingfseparated from the surrounding water. l

`The` above examples amply 4illustrate theprinciples of this invention. The invention vis appli- The emulsion of cable to a wide varietyof commercial organic f andinorganic liquids which are immiscible with each othenand which one may desire to sepa- `rate from van emulsied condition. The invention is particularly of value for use in grease trap equipment. It should be clearly understood however, that I do notV limit myself to the type of equipment used because any suitable mechanical means may be used for causing a uniform stream of an emulsion of immiscible liquids to contact a bed of surfaces. Similarly, any suitable means may be used to remove the separated components after theyhave been subjected to a separating treatment by the bed of surfaces by means of selective surface tension effects. The surfaces need not necessarily be in the form of circular pipes. Thus, a series of surfaces of anyshape may be properly mounted and spaced so that a stream vof emulsified materials or a mixture of liquids, as the casemay be, maybe passed over these surfaces. The chamber in lwhich the bed of surfaces is placed, the baffle `means for properly directing the stream, and the means for feeding and `removing the separated liquorscan all be varied to suit the vparticular installation without departing from the scope of the invention.

Without further elaboration, the foregoing will "so fully explain the gist of my invention that "others may, by applying current knowledge,

readilyadapt the same for use under varying conditions of service, without `eliminating certain features, which may properly be said to constitute the essential items of novelty involved, which items are'intended to be defined and secured to me by the following claims'.

I claim: s

1. A hydraulic ltering device for dispersions of liquid-liquid or `liquid-solid materials having different surface tensions comprising a chambered body provided withan inlet and an outlet,

a removable channeled 'element in said body, said channeled element adapted to receive the incoming mixture entering said inlet, and a plurality of parallelv pipes carried by and removable with said channeled element, said-pipes being provided withjvsurfaces having a selective surface tension separating effect whereby one of the i components of the mixture will be selectively accumulated about said surfaces to form ahydraulic filtering bed. i r 1 2. A hydraulic filtering device for d-ispersions of liquid-liquid or liquid-solid materials having different surface tensions comprising a chambered body provided with an inlet and an outlet, a plurality of substantially parallel ,pipes in said chambered body and provided'with surfaces having a selective surface tension separating effect, and means for removably mounting said pipes in spaced but grouped relation in the path of flow between said inlet and said outlet whereby to effect a substantial accumulation of one of the components of the dispersion between and about said pipes andfto form thereby a hydraulic filtering bed. y i

3. A hydraulic filtering device for dispersions of liquid-liquid or liquid-solid materials having different surface tensions comprising a chambered body, .provided with an inlet and an outilet, a pluralityof spaced elements provided withlsurfaces havinga selective surface tension separating effeet, a pair of spaced walls forming a longitudinal chamber into which the dispersion flows upon entering said chambered body through its said inlet, said'elements being supported by andl in 1crosswise-relation with'said spaced Walls; and -additi-onalf-walls providing-l a second channel lying substantiallyl paralleland adjacent to said elements; said second channel receiving-ther dispersion upon leaving *saidl first channell andffeed- -:ing the same to said elements.-

4. A hydraulic iil-terng-device-forA Idispersions or emulsions of liquid-.liquider liquid-solid ma- Aterials having difterentsurface tensions vcomprising Ia'chamberedvbody provided with an inlet-and v an outlet, a plurality of spaced elements provided vwith `surfaces having a, selective lsurface Vtension separatingweffect, a pair of;v spaced-walls formingr l a longitudinal chamber `'intcrwhich the-dispersion'ows `upon entering Asaid lchanrbered v body through its `said inlet, said elements'being Ysupi portediby.andjin'crosswise -relation*with said spaced ',"vvalls, and; additional` Wallsr providing a second `channel lying substanti'allyparallel and adjacent.: to said ele-ments, said second uchannel receiving-.the gdispersi-on upon-leaving- `saidfrst Vchannel and flowing. the. dispersion-ovariand upon 'said' *.elernents, said elements lying across'v said 'letjfor 'separating theijgrease` from the..Y .liquid :entering said inlet," 'the position fof said .outlet -below 'the 'topV ofsaid; -b-Odyld'eterinining" the nor- .imaljlquid rlevel. in" ithe ,bQ'dy tot provide. .an air 'i .tothe topvof. thesecond passage .tofconnect the @exteriorofsaidbodycommunicating 4Vwith said .air space .above said'. liquidlevelfwithsaid` second passage, said .second passageterminating *in-asa'id first '-.passage. vin .proximity fof` zitheflower jlimit.; .of said outlet, anda vent .connectiomleading tothe rstlpassage. y

8. A greaseatrap comprising .a hollow abodylhavl ing `an inlet, lan outletspacedtifroml said Linlet,

'means disposed between `said -inlet and. said out- 'let for separat-ing ythe greaseffrom l'the' liquidenteringss-aidf :inletgthe position of :said `c'iutle-t--flwlow which the' liquid separated fromfthe -g'reaseiiows -tofs-aid outlet; :a wallproviding afsec'ond passage lying within Vthe rlrst*'pass'age;` and-a=chamber communicating with `said second-passage, thre being'- an opening Vbetween vvsaid 'chamber andthe airspace above said normal-liquid-levelinifsaid v body, said 'chamber 'communicating' withsa'idsecond -passageat a point above said openingf' v9. A hydraulic ltering-device for dispersions of Vliquid-liquid yor liquid-solidma-terials having `different surfacey tensions-comprising af'ch-amvisp'ace therein abo-ve .said level, .a pass-age ve'xtend- 'ing downwar-dly'fromsaid outlet to communicate with said body near't'he lower portionjthereof, a wall providing ga, secondlpassage lying .within the iir'st, passage, ."there being. VVan. opening :adjacent to ,the .topioflthe second.. passagefto connectfthe .airspace above saldo-liquid 'level/With4 said secondvr .passage,.said secondgraissage:.terminatingv in. said first. passage in rproxmitywofdthe .flower.-,.linfiit,.4 of

saidoutlet. Y

- .LG... Agrease traplcomprisingafhollow 'bodyhavf -meansdisposedfbetween said inletfand said outlet fior-@separating ,the.-,`gr-easef.from: theeliquid Tenter- -v ring --said inlet,- .f they position-1 of saidvoutlet-.rbelo-w .the top "-ofsaid doody idetermining athen: normal vliquid level in the body tdprovidewan: airspace j ft'lierein 5 .above saidzxleveLs .apassagexxtending idownwardly .romr said .2 outlet?. to communicate xwitlrisaid .fb-ojdyfznearczthe.lower portion thereof,

ai fgwall: providing;v a secondi passage'iflying withinfthe'. dirstz: passagethere tbeingian opening adjacent '.to tithe latop @tithe/secondapassage?. to 'fconinfect llthe: air. space:above 1 said 'liquid level `with llsaid. secondl passagetfsaidi second pa'ssageltermif y#hating .1in saidi insti-'passage `in proximity of the *wall providingJ a lsecond passagellying withinthe rst #passageil there being -anf=openingffadjacent' bered-body provided-With an inlet-andan outlet,

means including a wall structure orred'ucing-the flow' of the dispersionprogressive'ly fbetween* 'said' inletandnsaid outlet,V a pluralityofi'elements having `sur-faces with -aiselect'ive surface-tension sepa`` --rating effect, means "for mounting. fsa'idf elements ingrouped "relation but spaced" from each other "in'the'vpath .of reduoediiowhetween: saidfinlet and said-outlet vto establish 1 a 1.substantialfacc'u- Vm'ulation of one-of'jthe components-ofthe dis- 1 Vpersion 1b etween fand-about l'said surfaces *ofi said lelements* tov form a hydraulic l-filtering bed, '-sa'id "lterng bed 'including sai-d-f'elements ing, an inlet, .an outletlspac'ed from `.said inletft45 i accumulation.

1103A hydraulic ltering 4device for dispersions -of 'liquid-liquid or liquidi-'solid materials having rdiilferent surface tensions comprisingfachambered body provided With-an inlet and-.ain outlet, apl-urality ofjpipesjhavingsurfaceswithxaselec- K tive surface tension separating. effect, meansffor inountingsaid '.pipes.\in.grouped ,relation "but vspaedjf from each other; inthe path bf Lflow'. be-

tween said inletand vsaid outlettopestablisha substantial accumulationofoneof the compo- -,ne`nts .of the .dispersion between and about`sa`id .surfacesof 4said pipes ato. Aforniti; hydraulic'iilter- 'ing' bed; :and .air..,separating means .mounted in .said -chambered..bodylandin the.. path E.Eofl flow vtending Ito.reducefthelzllowand .t-olliberate entrappeduair. -frommthe.idispersionrafter .-itent'ers 11.1A hydraulic lteringdevicefor dispersioniof -bers of channel formation in saidfgchamber'ed bodyr one of .saidmembers being Adispo sed.,aijsaid inlet( to receive the `incoming mixture ,andjtoifeed f the sameto aj` secondfmemlber; therefb-eingfmeans :associated j'with said'rstvfmemberfto. lreducethe ."lowgof said incomingfmixtu-re, andai-.plurality A.of

:elements shaving'v surfacesfvvith A selective-.surface tension separating effect-adapted .to contact-the -elements beingim .grouped :relationibut fsnaced from each other and mounted -adjacent said second member to allow .a substantial -accumulation of one of the components of the dispersion to form between and about said surfaces of said elements to establish a hydraulic filtering bed that includes said elem-ents and said accumulation.

12. A hydraulic filtering device for dispersion of liquid-liquid or liquid-solid materials having different surface tensions comprising .a chambered body provided with an inlet and an outlet, members of channel formation disposed adjacent to said inlet and in said chambered body, one of said members receiving the incoming mixture entering at said inlet and feeding the same to a second member, there being means associated with both of said members to reduce the flow of said incoming mixture, and a plurality of elements having surfaces with selective surface tension separating eifect adapted to receive the mixture from said second member, said elements being mounted in grouped relation but being spaced from each other to allow a substantial accumulation of one of the components of the dispersion to form between Iand about said surfaces of said elements to establish Ia hydraulic filtering bed that includes said elements and said accumulations.

'13. A hydraulic filtering device for dispersion of liquid-liquid or liquid-solid materials having different surface tensions comprising a chambered body provided With an inlet and an outlet, a member of channel formation disposed adjacent said inlet and in said ch-ambered body t-o receive the incoming mixture entering said inlet, baffle means to vchange the direction of ow of said mixture after it has passed through said member, and a plurality lof elements having surfaces With selective surface tension separating effect, said elements being arranged in grouped relation but spaced from each other, and me-ans adjacent said last means to flow said mixture over said surfaces to allow a substantial accumulation of one of the components of the -dispersicn to form between and about said surfaces o-f said elements to establish a hydraulic filter bed.

14. A hydraulic filtering device for dispersions of liquid-liquid or liquid-solid materials having different surface tensions comprising a chambered body provided with an inlet and an outlet, a removable channeled ele-ment in said body disposed adjacent to said inlet, said channeled element adapted to receive the incoming mixture entering said inlet, and a plurality of elements having surfaces carried in spaced relation by and removable with said channeled element, said surfaces having a selective surface tension separating effect to establish la substantial accumulation of one of the components of the dispersion between and about said surfaces to -form a hydraulic filtering bed.

15. A hydraulic filtering device for dispersions of liquid-liquid or liquid-solid materials having different surface tensions comprising a chambered body provided with an inlet and an outlet, a plurality of grouped but spaced parallel pipes in said chambered body and provided with surfaces having a selective surface tension separat- Iing effec-t, and means including a wall structure for reducing and -directing the flow of the dispersion over said pipes to establish a substantial accumulation of one of the components of the dispersion between and about said surfaces and to form thereby a hydraulic filtering bed.

'16. In the hydraulic filtration of the components of :a dispersion of insoluble materials having different sur-face tensions, the process of lemploying a group of elements having surfaces arranged in spaced relation to each other to subject the dispersion to a selective surface tension separating effect for one of the components to provide'thereby an accumulation of said component about said surfaces to form la hydraulic ltering bed, land maintaining said lter bed b-y controlling the rate of flow of said dispersion.

17. In the hydraulic filtration of the components of a dispersion of insoluble materials having different surface tensions, the process of employing .a plurality of elements having surfaces in grouped but spaced relation to subject the -d'ispersion to 'a selective surface tension separating effect for one of the components and creating thereby an accumulation of said component on and about said surfaces to form a hydraulic ltering bed, and maintaining said filter bed by controlling the rate of ow of said dispersion.

STEPHEN F. RESAN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 691,365 Dittler Jan. 21, 1902 990,959 Cresswell May 2, 1911 1,474,938 Marsh Nov. 20, 1923 1,537,260 Patrick May 12, 1925 1,591,852 MacArthur July 6, 1926 1,665,164 Gard et al. Apr. 3, 1928 1,804,743 Cannon May 12, 1931 1,873,597 Jones Aug. 23, 1932 `1,947,709 Garrison et al Feb. 20, 1934 1,955,064 Hawley Apr. 17, 1934 2,059,844 lBoosey Nov. 3, 1936 2,084,958 Hunter June 22, 1937 2,118,157 lC'amp May 24, 1938 2,137,421 l'Iark Nov. 22, 1938 2,214,248 Hawley Sept. 10, 1940 2,216,300 Shenk Oct. 1, 1940 v2,226,532 Hawley Dec. 31, 1940 2,228,353 Howes Jan. 14, 1941 2,324,190 Boosey July 13, 1943 2,346,435 Johnson Apr. 11, 1944 2,362,447 Boosey Nov. 14, 1944 2,405,838 Lawson et al. Aug. 13, 1946 `2,412,841 Spangler Dec. 17, 1946 FOREIGN PATENTS Number Country Date 9,770 Great Britain of 1913 OTHER REFERENCES Colloid yChemistry by Alexandria, vol. 1, page 233, 1926, vol. III, pages 41-48 and page 57, 1931. 

